Hi there and welcome to JA and thanks for the question.
Your vomiting....is it because you are activating your gag reflex with the brushing too far back on your tongue, or do you wake up nauseated?
Well, if you are vomiting for no reason (not brusing to far back and gagging yourself and you are not nauseated), then yes, you should have the testing done to see what is going on as vomiting for no reason is not normal. I
f you vomit daily, you have likely caused some esphageal irritation/damage from the acid/stomach contents coming up this frequently. I would have the test run the he/she is recommending.